1. Field of the Invention
The present invention relates generally to a two cycle engine and more specifically to a two cycle engine in which the crankcase is partitioned into a number of sub-compartments each of which communicate with a transfer passage.
2. Description of the Prior Art
JP-A-58-138221 discloses a previously proposed multi-cylinder 2 cycle engine of the type wherein measures have been exacted in an attempt to reduce the amount of residual combustion gases in the combustion chamber and to improve and/or stabilize combustion characteristics.
In this arrangement air is transferred from a crank chamber via a transfer passage to the combustion chamber in a manner wherein, upon the transfer port being opened (viz., the engine entering the induction phase), a flow of fresh air is injected into the combustion chamber for the purpose of scavenging the residual combustion gases from the combustion chamber and for providing fresh air with which the fuel, injected during the induction phase, can mix to form a combustible charge.
However, this arrangement has suffered from the drawback that each crankchamber additionally communicates with the combustion chamber of an adjacent cylinder by way of a conduit so that a small amount of air can be injected for the purposes of inducing swirl. This reduces the pressure in the crankcase and reduces the efficiency with which air is transferred via the main transfer passages.